Work to develop long-term cleanup strategy underway  

PHOENIX (Sept. 18, 2024) – The Arizona Department of Environmental Quality (ADEQ) officials today announced the successful completion of significant remedial actions at Senator Mine to protect the Hassayampa River and ensure public safety. Senator Mine is located in Yavapai County, 11 miles south of Prescott, Arizona, and situated on two private properties, each with one owner. The owners are Gold Paradise Peak, Inc. and Sino Vantage Group, Inc. 

“The urgency and severe threat of mine waste collapsing into the Hassayampa River necessitated swift and extreme measures,” said ADEQ Deputy Director Karen Peters. “I am pleased to report that our team was able to complete this tremendous undertaking, which successfully diverted around 800 feet of the Hassayampa River – a feat that has never been done before. This work was the critical first step in the ongoing effort to address the legacy impacts at this site. We are committed to ensuring the long-term safety of the Hassayampa River and its surrounding ecosystems.”

On June 28, 2024, ADEQ issued a determination of emergency under its Water Quality Assurance Revolving Fund (WQARF) program to undertake and fund immediate remedial actions to protect the Hassayampa River and ensure public safety | View >

Within just 90 days, ADEQ protected downstream communities by accomplishing the following emergency actions that addressed the immediate environmental threats posed by the mine drainage and unstable mine tailings:

• Obtained Clean Water Act Section 404 Permit: ADEQ collaborated with the local office of the U.S. Army Corps of Engineers and quickly obtained the permit necessary to conduct the emergency actions. 
• Installed French Drains: ADEQ installed French drains to divert mine-impacted water away from the tailings to prevent water from the mine from seeping into the tailings and waste rock piles.
• Installed Pipeline: ADEQ installed a 42-inch temporary pipeline approximately 800 feet long to divert the Hassayampa River's flow away from the tailings and waste rock piles.

ADEQ will carefully monitor and maintain the engineering features to ensure they function as intended as it continues to develop options for eventual remediation and cleanup of the Senator Mine site. This complex issue is expected to take years to resolve. ADEQ is committed to ensuring proper remediation of Senator Mine to protect public health and the environment and to restoring the Hassayampa River back to its original flow path.

The emergency response was triggered after ADEQ observed significant changes during a field visit on May 16, 2024. A concrete plug installed in a historic mine shaft (adit) redirected water into the mine’s tailings pile. This caused the tailings to become saturated, increasing the risk of collapse and potential contamination of the Hassayampa River. With monsoon season approaching, ADEQ took swift action to prevent erosion and protect the river from further harm. 

ADEQ will continue to hold the property owners accountable for developing and implementing a long-term solution. ADEQ remains committed to ensuring the complete remediation of Senator Mine to safeguard public health, protect the environment, and restore the Hassayampa River to its natural flow.

For more information about Senator Mine and ADEQ’s activities, visit the Senator Mine Permit of Interest page | View > 

Senator Mine is located on private property, and unauthorized visits may be considered trespassing, which is illegal. Mine adits, shafts, tailings, and waste rock may be unstable and dangerous. The Arizona State Mine Inspector’s office advises the public to “STAY OUT STAY ALIVE” | Arizona State Mine Inspector >

Contact

ADEQ Public Information Officer
Ph: 602-540-8072 (cell) 
Email >